Some fruits and vegs can now be stored in special containers that control the amount of O-2 and CO-2 they're exposed to prior to shipment. That helps to control the "respiration" of the product and defer rot. Once they're shipped to market, normal respiration occurs just like in fresh picked items. Preservatives, per se aren't added to produce.
If "PositivePatty" was trying to say that chain stores use preservative added produce, she's wrong. To say that any produce is meant to last for weeks is also totally wrong. Ironically, it looks like "PositivePatty" is positively wrong.
P.S. I gave Carolina Farmin a try on two separate occasions and their produce didn't last two days. Fresh produce should last at least a week.
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